Fig. 3

Integrated protein interaction network of the different parallel analyses. Ninety-two out of 151 differentially expressed proteins in SD are depicted in this figure, following their association (thin edges) with the top three GO enriched terms for each category (BP/MF/CC), and the protein–protein interactions (PPIs) derived from STRING database (thickness of edge according to interaction score). The remaining 59 proteins can be found in Additional file 2: Table S2. All GO terms include upregulated proteins, except for lysosomal lumen (CC) and catabolic process (BP). The nodes are colored according to the comparison to previously published proteomic datasets of FTLD and AD patients. This indicates half of the proteins depicted in this figure as potentially unique to SD (dark colored nodes), whereas the remainder (n = 48) was differentially expressed in the same direction in at least one of the FTLD/AD studies (light colored nodes). The 50 most strongly dysregulated proteins in SD are highlighted by thick border. A cluster of catenin and cadherin proteins – in the lower left corner – particularly stands out based on the PPIs, association with the GO terms adherens junction (CC) and cadherin binding (MF), and strong upregulation in SD (five out of six proteins in top 50). *The term ‘catabolic process’ was shortened from ‘glycos-amino-glycan catabolic process’. Abbreviations: GO = gene ontology; FTD = frontotemporal dementia; AD = Alzheimer’s disease; SD = semantic dementia